Dead Head here.
I'm not aware of Lesh ever playing a TBird on stage or for any recorded song although I think he did play a Gibson EB-0 very early in his career with the Dead. He is mostly known for his long history with Alembic and the custom Quadraphonic wall of sound they created for his stage performances with the Dead (independent tone shaping and output for each string on the bass, routed to high power dedicated channel amps powering a massive array of something like 32 speaker cabinets).
This is probably one of my favorite Lesh live recordings. He's using a much more modest sound system setup but still very interesting rack components. The bass is an Alembic as well.
Nice trippy laid back wandering signature Dead Head sound.
Here's a link to a very interesting short read on how his music and gear evolved...
Phil Lesh Tone & Sound – Bass Guitar Gear Guide - Jam Buzz
Enjoy.